With conventional combine harvesters, the crops that are severed by the header are conveyed to a threshing and separating assembly where a rotor is rotated within a generally cylindrical chamber to thresh the crop. Grain, seed, or the like, is loosened and separated from the other crop material and falls onto a grain pan of a cleaning assembly, which typically includes a pre-cleaning sieve disposed above a second grain pan. The cleaning system typically includes a set of stacked sieves or shoes that are reciprocally moved, usually in the fore and aft directions, to separate or sift the grain from tailings and material other than grain (MOG). With many combines, as the grain is cleaned from the MOG, it falls through the sieves and drops onto or into one or more underlying clean grain pans that are disposed below the sieves, which pans typically include a plurality of elongated and longitudinally oriented clean grain collecting troughs positioned side-by-side across at least a portion of the width of the combine to receive the clean grain that falls through the set of sieves. Such collecting troughs are configured to receive the grain falling therein and to convey such grain therethrough towards an intersecting, cross, generally laterally extending, clean grain conveyance trough.
The laterally extending clean grain conveyance trough has a conveyance mechanism, often in the form of an auger, for moving and delivering the clean grain to an elevator that carries the clean grain up to a clean grain tank. For convenience of reference, the clean grain conveyance trough is referred to herein as the clean grain auger trough regardless of the particular conveyance mechanism that may be employed therewith for moving the clean grain through such trough.
During vibration of the sieves, air is blown upwardly and rearwardly through the sieves to carry lighter elements of the MOG, or chaff, away. The heavier elements and tailings that are too large to fall through the sieves and too heavy to be blown away are caused to be moved by the vibrations, generally rearwardly along the top surfaces of the sieves, towards and over rear edges of the sieves to fall onto a tailings pan located below and extending somewhat beyond such rear edges. The tailings pan, similarly to the clean grain pan, typically includes a plurality of elongated and longitudinally oriented tailings collecting troughs positioned side-by-side across at least a portion of the width of the combine to receive the tailings that fall from the rear edges of the sieves. The collecting troughs receive and convey the tailings towards an intersecting tailings conveyance trough.
The sidewardly extending tailings conveyance trough receives and conveys the tailings with a conveyance mechanism, often in the form of an auger extending therethrough, to a tailings return conveyor that carries the tailings upwardly, back to the cleaning or separating system of the combine, for reprocessing. For convenience of reference, the tailings conveyance trough will generally be referred to herein as the tailings auger trough regardless of the particular conveyance mechanism that may be employed for moving the tailings through such trough.
Although the clean grain auger trough and the tailings auger trough are generally effective in conveying and emptying the clean grain and tailings from the respective troughs, remnants of such materials, as well as dirt and other residue, can build up over time along the bottoms and edges of the auger troughs and at locations beyond the reach of the augers that extend through such auger troughs. This problem is exacerbated when moisture is introduced into the auger troughs and/or such remnants remain in the troughs as they are exposed to weather extremes. It is desirable to be able to remove as much of such remnants as possible, especially from the clean grain auger trough, to avoid in subsequent harvesting operations the mixture into the newly harvested grain of grain from an earlier harvesting and to avoid the fouling of the auger or other conveyance mechanisms in the auger troughs.
In combines, the ability to clean out the troughs has been essentially limited to the introduction of a pressurized stream of water into the end of an auger trough to try to wash out the remaining remnants, with modest success. In order to better clean out the auger troughs, some users have cut holes into the bottoms of the troughs, generally of limited size and somewhat centered along the length of troughs, to provide an access point for the introduction of pressurized streams of water or air and to permit access through such holes for manual clean out of at least some of the remnant material. After the clean-out process, the holes were sealed with removable plates mounted to the troughs to cover the holes during the subsequent operation of the combines. The plates thus functioned essentially as panels or doors along the undersides of the troughs.
More recently, some combines have been designed with auger troughs that include engineered doors along portions of the bottoms of the troughs, generally centered along the length of the troughs and designed to provide a tighter and more uniform fit as compared to the user-crafted panels. By removing bolts or like connector assemblies securing the doors to the troughs, a user could remove the doors to permit cleaning activities and could later reinstall such doors, again from beneath the combines.
Even with the engineered clean-out doors, the clean-out process has remained problematic due to the difficulties associated with the removal and re-installation of such doors and location of the doors beneath the combine. Often, the operator must access the doors while lying directly beneath the combine. When the doors are removed, the remnants typically fall onto the operator. The doors are unwieldy, particularly when handled while lying on one's back in a field. Since the doors encompass only a portion of the underside of the troughs, even when such doors have been removed for clean out activities, remnants of crop and other materials may remain at the ends of the troughs and at other areas along the troughs that are not located above the door locations or to which there would be only limited, if any, accessibility through such doors.
U.S. Pat. No. 7,585,213 describes an improved auger clean-out door wherein a rigid, removable door panel is engaged with and supported by the auger side walls, with the door extending essentially along the length of the auger trough. Engagement features at the ends of the panel ensure that the panel stays in place. These rigid (typically welded) panel assemblies are, however, adversely affected by a variety of normal manufacturing conditions that often cause the mating parts to have a poor profile match, such conditions including forming variability, welding (heat) distortion, deformation due to shipping and handling, and so forth. A poorly matching profile greatly increases the difficulty in assembling/servicing, and may cause poor sealing that results in grain loss/damage.
An improved auger trough that facilitates an easier and more effective clean-out without the necessity of an operator accessing the trough from beneath the combine would be a welcome advancement in the industry.